"haemal cavity" meaning in English

{
  "forms": [
    {
      "form": "haemal cavities",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "haemal cavity (plural haemal cavities)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
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          "source": "w"
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          "source": "w"
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        {
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        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Anatomy",
          "orig": "en:Anatomy",
          "parents": [
            "Biology",
            "Medicine",
            "Sciences",
            "Healthcare",
            "All topics",
            "Health",
            "Fundamental",
            "Body"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "The thoracic-abdominal cavity, containing the heart, etc."
      ],
      "id": "en-haemal_cavity-en-noun-rNh6BCzJ",
      "links": [
        [
          "anatomy",
          "anatomy"
        ],
        [
          "thoracic",
          "thoracic"
        ],
        [
          "abdominal",
          "abdominal"
        ],
        [
          "heart",
          "heart"
        ]
      ],
      "raw_glosses": [
        "(anatomy) The thoracic-abdominal cavity, containing the heart, etc."
      ],
      "topics": [
        "anatomy",
        "medicine",
        "sciences"
      ]
    }
  ],
  "word": "haemal cavity"
}

{
  "forms": [
    {
      "form": "haemal cavities",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "haemal cavity (plural haemal cavities)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        "English countable nouns",
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        "English lemmas",
        "English multiword terms",
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        "en:Anatomy"
      ],
      "glosses": [
        "The thoracic-abdominal cavity, containing the heart, etc."
      ],
      "links": [
        [
          "anatomy",
          "anatomy"
        ],
        [
          "thoracic",
          "thoracic"
        ],
        [
          "abdominal",
          "abdominal"
        ],
        [
          "heart",
          "heart"
        ]
      ],
      "raw_glosses": [
        "(anatomy) The thoracic-abdominal cavity, containing the heart, etc."
      ],
      "topics": [
        "anatomy",
        "medicine",
        "sciences"
      ]
    }
  ],
  "word": "haemal cavity"
}